Garage door operators that directly connect to sectional garage doors are well known and must have a manual disconnect that allows the operator to be disconnected from the door. The disconnect mechanism is required to make it possible to operate the door manually in the case of power failures, fire, or emergency situations where entrapment of a person or object occurs. In these instances, the disconnect operates to allow manual displacement of the door to free any obstruction beneath the door or make it possible to enter or exit the structure.
In a trolley-type operator, the manual disconnect is typically a rope extending from the trolley with a handle as will be described below. The majority of motorized operators for residential garage doors employ the trolley-type system. These systems apply force to a section of the door powering it between the open and closed positions. In normal situations, the trolley-type door operator directly connects to the top section of a segmented garage door, and, for universal application, may be powered to operate doors of vastly different size and weight, even with little or no assistance from a counterbalance system. As its name suggests, the trolley-type mechanism has a trolley that operatively connects the top section of the door to the motor. As the door moves between the opened and closed positions, the trolley translates along a track toward the rear and front of the garage, respectively. The disconnect rope for trolley-type operators is typically suspended from the trolley and operates to disconnect the operator from the top door section.
The disconnect rope and handle must extend within six feet of the floor to permit grasping and actuation by a person. In the case of a garage opening for a single car, the centrally-located disconnect rope and handle, being positioned medially, can catch on a vehicle during movement or be difficult to reach due to its positioning over a vehicle located in the garage. As a further detriment, placement of the disconnect rope on the trolley over the vehicle makes it difficult to find the rope in a darkened garage during a power outage or the like.
In terms of security, the trolley's movement places the rope closest to the garage door opening when the garage door is closed. When windows are added to the top section of the garage door, a window may be broken, and the disconnect, easily within reach of an intruder, may be used to separate the operator from the door preparatory to manually opening the garage door.
A separate concern is created by other known disconnects that are weighted or sprung toward the connected position. The spring or leverage must be overcome to operate the disconnect such that the door can be moved. These biased disconnects allow for automatic engagement of the disconnect when the door is manually moved to the original position of the door, i.e., the position where the disconnect was disengaged. In some bias disconnects, the disconnect will automatically engage when the trolley is moved by the motor to the position that the door was in. Disadvantageously, a user will have to wait until the trolley is in the former position in order to engage a disconnect mechanism. This type of system is very limiting because the trolley will engage the disconnect in only one position. Furthermore, the user is unable to control engagement of the disconnect mechanism, as the mechanism automatically engages as soon as the trolley reaches the disengagement position. This automatic disengagement prevents manually moving the door a short distance and then manually engaging the disconnect mechanism at the new position, which may be useful when an object is lodged beneath the door.